The ever-increasing demand for smaller sized electrical devices, such as cell phones, digital cameras, tablet computers, personal digital assistants (PDAs), vehicle electronics, etc. has triggered a corresponding need for smaller sized photography modules contained within the device. Such modules may include optical imaging lenses, module housing units, image sensors, etc. Size reductions may be achieved from various aspects of the electrical devices, which may include not only the charge coupled device (CCD) and the complementary metal-oxide semiconductor (CMOS), but also the optical imaging lens mounted therein. When reducing the size of the optical imaging lens, however, achieving good optical characteristics may become a challenge. Furthermore, achieving a high view angle and a great aperture size are important in certain applications, such as situations where a photography module is used in vehicles.
In light of the above issues, designing an optical imaging lens with a shorter length is not easily achieved by merely decreasing the size of each element proportionally. This is especially true for an optical imaging lens mounted with five lens elements, in which the distance between an object-side surface of the first lens element and an imaging plane along an optical axis may be great. Size reductions of an optical imaging lens cannot be achieved simply by proportionally shrinking the size of each element therein. Various aspects of the optical imaging lens, such as production difficulty, yield, material property, etc. should be taken into consideration.
Therefore, production of a size-reduced optical imaging lens presents higher technical barriers and challenges than that of a conventional lens. Accordingly, achieving good optical characteristics in view of the various relevant considerations and technical barriers is a challenge in the industry.